1. Field of the Invention
The present invention relates to a handheld surface coordinate measuring device, preferably for measuring and/or marking coordinates on wall surfaces in the constructional industry, and to an associated measuring method.
2. Description of the Prior Art
With respect to a surface, the coordinates of a spatial point that is generally defined in three dimensions are designated as surface coordinates. Usually, a local Cartesian surface coordinate system, which is defined within the surface, is used for this purpose, preferably with the point of origin at a corner point and at least one coordinate axis along an edge of the surface.
Particularly in the constructional industry, the measurement and marking of surface coordinates on wall surfaces, which includes, within the meaning of the invention, surfaces of side walls, ceilings, floors, etc. that are at least partially planar, play an important role, e.g., for positioning fastening points. In side walls, the inner edges usually extend approximately horizontally or vertically for the most part.
Measuring and/or marking of surface coordinates on wall surfaces is traditionally carried out by using a folding measuring rod successively in one of two directions extending perpendicular to one another for measuring the distance from a virtual intersection to the closest inner edge. Besides the uncertainty of the virtual intersection, the time spent on a twofold measurement is also disadvantageous.
German Publication DE 3839797 discloses an electrooptical distance measuring system for laying out demarcations and which is combined with a horizontal measuring system and a vertical measuring system.
German Publication DE 19643800 discloses a marking device which cooperates with a rotating laser to generate marks for fastening points on a wall surface and which are spaced apart equidistantly along a line. German Publication DE 10034035 discloses a marking device of this kind and which compensates for a positioning error of the housing within a tolerance range.
According to Swiss patent CH 691330, a portable rotating laser is combined with a laser distance measuring system and an angle measuring system so that, in addition to generating virtual planes, the position of a reflecting auxiliary device in three-dimensional space can be determined indirectly within the virtual plane. A rotating laser of this type is not suitable for direct measurement and/or marking of surface coordinates on wall surfaces.
In addition, U.S. Pat. No. 6,202,312 discloses an optical marking device which projects two fanned out laser beams extending perpendicular to one another in a wall surface.